The etiology of the chronic urinary tract (UT) disease, interstitial cystitis, is obscure. The objective of the proposed research is to develop a suitable UT epithelial cell model by culturing normal human bladder and/or ureter uroepithelial (UE) cells in a serum- free medium. We also propose to employ this novel cell model to investigate the effect of bacterial-UE cell interactions on several different parameters affecting the capacity of the epithelial cells to transduce ligand-receptor binding signals. We plan to study the activation/inhibition of protein kinase-C (PK-C), and the induction/suppression of ornithine decarboxylase (ODC) before and after perturbation of the UE cells. Additional experimental protocols are designed to evaluate the effect of extrinsic cell signal modulators (e.g., bacterial adherence, bacterial and urinary metabolites, bacterial lipopolysaccharides) on the biosynthesis of proteoglycans. Experimental protocols are designed to investigate the effect of epidermal growth factor and steroid hormones (aldosterone, 17-beta-estradiol, testesterone, and progesterone) on signal-transducing enzymes, ODC and PK-C, and on the receptivity of UE cell binding to pathogenic bacteria (Escherichia coli, Proteus mirabilis, and Staphylococcus aureus). Lastly, we propose to investigate the effect of bacterial adherence, growth factors, hormones and the cyclophosphamide urinary metabolite, acrolein, on ion transport of UE cells in culture. In particular, experimental protocols are designed to study the regulation of both cation (Na+, K+), and anion (Cl-, and SO42-) uptake/efflux through the apical and basolateral surfaces of UE cells. We believe that these varied experimental protocols should provide new insights into the pathogenic mechanisms contributing to dysfunction of normal human UE cells of the bladder and UT.